The edible fungi species of the genera Morchella are known by their ascocarp or fruiting body. The ascocarp represents the mature embodiment of the sexual reproduction cycle of the morel and is lined with tiny, microscopic elongated sacs, each of which is called an ascus. Inside each ascus are microscopic spores lined up like small eggs, approximately eight spores per ascus. These spores escape from the lid of the ascus and take to the air marking the beginning of the life cycle of the morel mushroom. When the spores land on an appropriate food source, such as moist, dead, rotting, or decaying plant life, the spores will “hatch” producing small hair-like structures called hyphae. The hyphae begin to spread throughout the food source producing an interwoven mat or feeding network called mycelium. The hyphae's absorption of nutrients from the non-living food source demonstrates the saprophytic nature of the morel. Under certain, unfavorable conditions, this mycelium contracts to form hardened protective bodies called sclerotia. The sclerotia then lie dormant until favorable conditions arise. During favorable conditions, the sclerotia develop ascocarps.
The ascocarps of the Family Morchellaceae, especially those of morchella esculenta, morchella deliciosa, morchella crassipes, elata, semi-libria, and morchella angusticeps “black” have been highly sought after for many years and are considered to be the most delicious of all mushrooms. Every spring thousands of morel hunters take to the woods in search of the ever-elusive morel, also known as the “sponge mushroom.” In fact, certain towns in Michigan hold mushroom festivals every spring to celebrate the opportunity to take to the woods and find this delicious morsel. Unfortunately, the fruiting of the morel occurs naturally only under select conditions, thereby limiting the availability of this highly sought after delicacy.
In addition, the sclerotia themselves are also a sought-after delicacy. Unfortunately, because naturally-occurring sclerotia are formed underground, they are difficult to locate and harvest. In fact, the harvesting of Morchellaceae sclerotia often requires the use of trained animals, such as dogs. Due to the difficulty in locating and harvesting Morchellaceae sclerotia, the cost of such sclerotia is extremely high.
Processes centered around the saprophytic nature of the morel have been suggested for commercially cultivating morels. Such processes include that described in U.S. Pat. No. 4,757,640. However, these processes have not proven to be successful in the commercial production of these mushrooms or the sclerotia, either in the field, or in environmentally controlled conditions.